Telegraph Sport looks at five key stages where the 101st edition of the Tour
de France can be won or lost

The old adage that the Tour de France cannot be won on the the opening weekend, but can be lost, will not be lost on the riders on the lumpy second stage from York to Sheffield.

With a course resembling that of Liège-Bastogne-Liège, don't be surprised to see a tough puncheur such as Joaquim Rodríguez, Alejandro Valverde or even Peter Sagan to prevail.

With its tight winding roads, a nervous peloton will fight for position on the heavy Yorkshire tarmac and be mindful of the opening stage of the 2011 edition, when Alberto Contador saw his title challenge all but end after he was caught up in a crash.

The last time the Tour hit the cobbles of northern France, Frank Schleck saw his title ambitions come to an abrupt end after falling hard on the pavé.

While the route, with nine sections of treacherous cobbles (below graphic), will play into the hands of one-day classics speciallists such as Fabian Cancellara or reigning Paris-Roubaix champion Niki Terpstra, for general classification riders such as Chris Froome and Contador riding with caution will be the order of the day.

Finishing on La Planche des Belles Filles, the scence of Froome's first Tour stage win in 2012, stage 10 looks to be the defending champion's first opportunity to take the maillot jaune, or leader's yellow jersey, at the end of the tough 161-kilometre stage from Mulhouse.

With seven climbs on the Bastille Day stage, including the steep ascent of the penultimate Col des Chevrière, the general classifiaction can expect a severe shake-up here as the climbers are given their first chance to test themselves.

Though relatively short at just 145.5km, stage 18 could prove decisive in the final reckoning in the general classification.

The tough hors catégorie ascent of the Col du Tourmalet may see contenders attack the maillot jaune, while the final climb up the Hautacam is almost sure to see fireworks on the penultimate day in the mountains.

After passing through three mountain ranges - the Vosges, Pyrenees and Alps - the riders will face their only time trial of the three-week stage race.

Should Froome remain in the race, and in either the maillot jaune or within a minute of the leader, the penultimate stage could be the day where the winner is decided, as it was in 2011 when Cadel Evans overhauled Andy Schleck in the 'race of truth'.

At 54km, world time trial champion Tony Martin will be eyeing the stage win, though Froome can expect to place high in the day's standings.